By the late 1960s, Marquand had begun a career writing and directing television documentaries for the BBC, where he worked on projects such as the 1972 series Search for the Nile and an edition of One Pair of Eyes (1968),[2] about the novelist Margaret Drabble who had been a friend of his at Cambridge.[3] He collaborated with the celebrated foreign correspondent, James Cameron, (not to be confused with the director) on a long running series called "Cameron Country" for BBC TV and also with John Pilger on a series of films for ITV. In 1979, Marquand incorporated many of his documentary techniques in his biographical television movie Birth of the Beatles.

On the strength of his direction of the 1981 feature, Eye of the Needle, Marquand was hired by producer George Lucas to direct Star Wars Episode VI: Return of the Jedi.[4] In his commentary track on the DVD, Lucas explains that Marquand "had done some great suspense films and was really good with actors. Eye of the Needle was the film I'd seen that he had done that impressed me the most, it was really nicely done and had a lot of energy and suspense." Marquand is the only non-American to have directed a Star Wars movie.